In your construction, the meaning of on is approximately using. That's to say, he filled up [his car fuel tank] on / using / with fuel. Same as if you're still hungry, fill up [your stomach] on / with.

In the following example, do they have the same meaning? I'll fill the form tomorrow. I'll fulfill the form tomorrow. How to pronounce feel, fill, or feeling correctly? Ask question asked 7 years, 10 months ago modified 6 years, 6 months ago

Ask question asked 7 years, 10 months ago modified 6 years, 6 months ago